Amazon cant find my shipment, yet courier shows as delivered, but they wont refund.

Ive tried reconcile and provided documentation, but they just keep replying the same :

We have completed an additional check in response to your request. We have no record of receiving the following expected items: X003PUOLJJ / -41 (this is all of my shipment)

I have tried asking several different questions but every time they reply with exactly the same email, word for word, with no mention/regard to my latest question. I think AI could do a better job than this copy pasta.

This was my biggest shipment yet, and is a huge set back for me as the manufacturer and being in Australia, it takes well over a month from shipment date for me to get a shipment stocked into FBA for sale. Plus manufacturing and packaging time, my (only) listing has now been out of stock for 2 months waiting for this to arrive and then go through the process of them finally telling me they couldnt find it after waiting nearly a month after ETA for them to allow opening a case about it.

I also have stock that amazon oversold, so paid buyers waiting for the delivery as well as fees for out of stock listing... In my view if they are saying they got nothing yet the courier shipment details show a significant weight difference, and it was addressed to the place they asked to, they should cover the costs, even offering insurance for this sort of thing.

This really makes me reconsider choosing to sell on amazon, and thet I may well just stick to ebay where i started and still sell.

My case is 15380056241, for shipment FBA17WKD764B